Evolution of the Visual System -- An Organ of Exquisite Perfection -- Photoreceptor Structure, Function, and Development -- Development of the Foveal Specialization -- An Update on the Regulation of Rod Photoreceptor Development -- The Retinal Pigment Epithelium and the Visual Cycle -- Photoreceptor-RPE Interactions -- Molecular Biology of IRBP and Its Role in the Visual Cycle -- Visual Signaling in the Outer Retina -- Regulation of Photoresponses by Phosphorylation -- The cGMP Signaling Pathway in Retinal Photoreceptors and the Central Role of Photoreceptor Phosphodiesterase (PDE6) -- Rhodopsin Structure, function, and Involvement in Retinitis Pigmentosa -- Multiple Signaling Pathways Govern Calcium Homeostasis in Photoreceptor Inner Segments -- The Transduction Channels of Rod and Cone Photoreceptors -- Rhodopsins in Drosophila Color Vision -- INAD Signaling Complex of Drosophila Photoreceptors -- Visual Processing in the Inner Retina -- Visual Signal Processing in the Inner Retina -- Color Vision and Adaptive Processes -- Human Cone Spectral Sensitivities and Color Vision Deficiencies -- Luminous Efficiency Functions -- Cone Pigments and Vision in the Mouse -- Multifocal Oscillatory Potentials of the Human Retina -- Aging and Vision -- The Aging of the Retina -- Aging of the Retinal Pigment Epithelium -- Visual Transduction and Age-Related Changes in Lipofuscin -- Nonphotoreceptor Light Detection and Circadian Rhythms -- A Nonspecific System Provides Nonphotic Information for the Biological Clock -- The Circadian Clock: Physiology, Genes, and Disease.